Salmonellosis in two dairy herds associated with a sewage farm and water reclamation plant

Two dairy herds, situated on a sewage farm, were monitored for the presence of salmonellas following outbreaks of Salmonella dublin infection. In addition an S. dublin control scheme, which involved examination of adult animals and calf vaccination, was instigated. During the period 1975-84, 12 salmonella serotypes and 10 phage types of S. typhimurium were isolated from the cattle and their environment although their presence was seldom associated with disease. Two adult S. dublin excreters were detected but it was concluded that none of the tests employed to examine the adult animals was sensitive enough. The prevalence of disease in the calves was low and although vaccination may have been beneficial it did not eradicate S. dublin infection. Thus S. dublin persisted in adults and calves during the 8-year period but its presence was seldom associated with disease. The results are discussed with regards the disease risk to animals from the agricultural use of sewage sludge and the public health aspects.     

Salmonella saint-paul infection in two dairy herds.

An outbreak of salmonellosis due to Salmonella saint-paul in two dairy herds was first detected during routine examination of calves soon after calving; infection reached 100% amongst calves and up to 60% amongst milking cows. Excretion by cows continued for over 12 months and by calves for up to 18 months. The most important factor in controlling the spread of infection was reduction of environmental contamination by removal of carriers, prompt antibiotic treatment of sick calves and reduction in stocking densities.     

Salmonella saint-paul infection in two dairy herds

An outbreak of salmonellosis due to Salmonella saint-paul in two dairy herds was first detected during routine examination of calves soon after calving; infection reached 100% amongst calves and up to 60% amongst milking cows. Excretion by cows continued for over 12 months and by calves for up to 18 months. The most important factor in controlling the spread of infection was reduction of environmental contamination by removal of carriers, prompt antibiotic treatment of sick calves and reduction in stocking densities.     

Salmonellosis associated with 'Combi-oven' cooked egg.

During July 1989, four cases of Salmonella enteritidis (later identified as PT24) infection were reported by laboratories in Bristol. All those infected had dined at a restaurant in the city. An epidemiological investigation revealed that a number of restaurant staff and 56 customers who had completed a questionnaire had also been ill with gastrointestinal illness. An association was found between illness and eating egg mayonnaise. A 'Combi-oven' egg-cooking technique has been identified as the most likely cause of this outbreak. In view of the widespread commercial use of this cooking method the evidence related to this outbreak is given in detail.     

Illness in a community associated with an episode of water contamination with sewage.

Following an episode of water contamination with sewage in a rural Irish town, a community-wide survey of gastrointestinal-associated illness and health service utilization was conducted. Random sampling of households yielded residents who were surveyed using a self-administered questionnaire. Of 560 respondents from 167 (84%) households, equal proportions lived in areas known to have been exposed and unexposed to the contaminated water, although 65% of subjects reported using contaminated water. Sixty-one percent of subjects met the case definition. The most common symptoms among cases were abdominal cramps (80%), diarrhoea (75%), appetite loss (69%), nausea (68%) and tiredness (66%). Mean duration of illness was 7.4 days. Only 22% of cases attended their general practitioner. Drinking unboiled water from the exposed area was strongly associated with being a case. A substantial degree of community illness associated with exposure to contaminated water was observed. The episode ranks as one of the largest reported water-borne outbreaks causing gastrointestinal illness in recent times.     

Comparative prevalence of tuberculosis in two dairy herds in India

Holstein Friesian cows and their crossbred progeny on a farm in northern India were tested for tuberculosis (TB) infection using a single intradermal tuberculin test. The results showed that the animals persistently harboured TB infection for periods of two to four years. The recent comparative intradermal tuberculin test revealed that at least five out of nine of these cattle reacted positively to bovine tuberculin purified protein derivative. A high (15.76%) prevalence rate resulted because none of the infected animals had been segregated or culled from the herd since the first incidence was detected in 1992. In contrast, another farm in western India that practiced segregation and culling was able to contain the level of prevalence of TB between 0.65% and 1.85%. These findings call for stricter regulations on the management of TB at farm, state and country level and a revision in the mode of breeding programmes adopted by farms.     

Salmonellosis in wild birds feeding at sewage treatment works.

Between June 1976 and August 1977 faeces were collected from 599 wild British birds caught during ringing operations at two sewage treatment works in south-east England. Samples were incubated with selenite-F broth to detect the presence of Salmonella. Salm. anatum was isolated from one bird, a Dunnock Prunella modularis an incidence of 0.17% of the total birds examined and 3.23% of the Dunnocks. Comparisons are drawn with previously reported studies and it is suggested that sewage treatment works play little part in the transmission of Salmonella infections to wild birds feeding there.     

Arcobacter cryaerophilus and thermophilic campylobacters in a sewage treatment plant in Italy: two secondary treatments compared.

Microaerophilic organisms were monitored in sewage effluent undergoing two secondary treatments: air and oxygen-activated sludge. The mean numbers of Arcobacter cryaerophilus and thermophilic campylobacters detected in incoming sewage were 5639/100 ml and 1720/100 ml respectively. Secondary treatment in air tanks reduced the population of A. cryaerophilus by 97.1% and of thermophilic campylobacters by 99.08%, whereas treatment in oxygen tanks reduced the bacteria 97.8% and 99.63% respectively, showing that oxygen-activated sludge treatment was more effective. Subsequent tertiary treatment with 2 p.p.m. chlorine dioxide evidenced the removal of A. cryaerophilus to 99.9% and eliminated thermophilic campylobacters. Campylobacter jejuni and C. coli constituted 54.1% and 45.9% of 74 thermophilic campylobacter strains isolated. In air-activated sludge effluent C. jejuni was found more often, thus appearing more sensitive to oxygen. The most probable number assay used for detection of campylobacters, blood medium for enrichment and blood-free medium for plating, also appeared to be fit for A. cryaerophilus, the high density of which in urban sewage may be due to inflows from slaughterhouses.     

Epidemiology of BHV 1 virus infections in dairy herds.

The epidemiology of bovine herpesvirus 1 (BHV 1) infections was studied in 20 dairy herds. Periodic serological surveillance of these herds during three consecutive years (1980-82) was combined with clinical studies. In 19 herds seropositive cows were found indicating previous exposure to BHV 1. One herd had its first experience with BHV 1 during the study. No indication of virus circulation for at least three years was found in eight herds. In five herds an interval of 2 years without an indication of virus circulation was followed by infections in yearlings, first- and second-calf cows during the third year. One or two cycles of virus circulation in calves and/or yearlings during the 3 year survey were detected in six herds. Most BHV 1 infections passed unnoticed. Signs of respiratory disease in association with BHV 1 infection were observed in three herds: young animals were most seriously affected. Clinical manifestations of BHV 1 infections were less pronounced than a few years ago when infections in cows caused frank signs and diagnosis was frequently possible on the basis of a typical clinical picture. BHV 1 was the cause of abortions in the herd that experienced its first infections during this survey. A survey of the age-specific BHV 1 neutralizing antibody pattern may be helpful for tracing animals and herds at risk of an outbreak of infectious bovine rhinotracheitis.     

Salmonellosis associated with pet turtles--Wisconsin and Wyoming, 2004

Salmonellosis associated with small pet turtles in the United States was a major public health concern in the 1970s. In 1975, the Food and Drug Administration (FDA) banned commercial distribution of small turtles (i.e., those with a carapace of <4 inches). The FDA ban prevents an estimated 100,000 cases of salmonellosis among children each year. However, a recent resurgence in the sale of small turtles has generated concern. In Wisconsin and Wyoming, at least six human cases of salmonellosis have been linked to such turtles. This report describes the investigation into those cases. The findings underscore the need for health and environmental officials to prevent illegal distribution of small turtles and consider patient contact with turtles when investigating salmonellosis cases.     

郑州市某污水处理厂尾水毒性评价

目的探讨郑州市某污水处理厂进出水的急性毒性和遗传毒性。方法采集该厂进水、二级出水和三级出水,利用发光细菌毒性测试法检测进出水的急性毒性,利用蚕豆根尖微核试验检测进出水的遗传毒性。结果进水、二级出水和三级出水对发光菌的抑光率分别为(33.96±7.51)%、(14.32±7.36)%、(7.24±5.58)%,二级出水和三级出水对发光菌的抑光率低于进水(F=12.159,P=0.008)。蚕豆根尖微核细胞率分别为(12.67±2.08)‰、(6.33±1.53)‰和(2.67±0.58)‰,污染程度分别为重度污染、轻度污染和基本无污染,二级出水及三级出水蚕豆根尖微核细胞率低于进水(F=56.850,P<0.001)。结论进水经处理后急性毒性及遗传毒性显著下降,但对环境仍具有一定的生态风险性。     

Salmonellosis associated with chicks and ducklings--Michigan and Missouri, Spring 1999

During the spring of 1999, outbreaks of salmonellosis associated with handling chicks and ducklings occurred in Michigan and Missouri. This report summarizes the epidemiologic information for the outbreaks and provides an overview of legislative efforts to control the distribution of chicks and ducklings. These outbreaks demonstrate that handling chicks and ducklings is a health risk, especially for children, and highlight the need for thorough handwashing after contact with chicks, ducklings, and other young fowl.     

Pontiac fever at a sewage treatment plant in the food industry.

BACKGROUND AND OBJECTIVES: During a hot and humid summer period workers became ill with fever and flu-like symptoms after repairing a decanter for sludge concentration at a sewage treatment plant. The work took place over a period of 10 days in a small closed room, while another decanter was in operation and was consequently emitting aerosol to the environment, to which the workers were exposed. The aim of this study was to determine the cause of this outbreak of febrile illness so that additional cases could be prevented. METHODS: All 5 patients were seen and examined in the Department of Occupational Medicine. Furthermore 2 of the workers had recurrent illness and were examined during hospitalization. As Pontiac fever (nonpneumonic legionellosis) was suspected, antibodies to legionellae were measured in blood samples. After positive antibody titers to Legionella pneumophila were found, samples of the sludge were collected for legionellae culture. RESULTS AND CONCLUSIONS: The clinical picture agreed with that described for Pontiac fever, and positive antibody titers to L. pneumophila serogroup 1 were found in blood from all 5 patients. L. pneumophila serogroup 1 was cultured in high amounts from sludge from the decanter. It was concluded that the fever was caused by L. pneumophila emitted to the environment by the uncovered decanter. Procedures for preventing new cases were established.     

Symptomatology of children in contact with sea water contaminated with sewage.

STUDY OBJECTIVE--The aim was to determine whether or not there was a measurable risk of ill health associated with contact with sea water for children between the ages of 6 and 11 years old. DESIGN AND SETTING--This was a prospective survey carried out on Blackpool beach. Parents of children between the ages of 6 and 11 years were interviewed over a seven week period during July, August, and September, 1990. Respondents were followed up 10-14 d after the original interview by either telephone or post. Water samples were collected on each day of the survey. PARTICIPANTS--939 interviews with parents or guardians were completed on the beach; 857 (91.9%) of these persons agreed to a follow up interview. The results of this study are based on 703 cases of matched data, of good quality, collected for each child on the beach and during a follow up interview. MAIN RESULTS--Non-compliance with the European Community microbiological imperative standards for recreational waters at Blackpool Tower and South Pier sampling sites, respectively, ranged between: 6% and 7% for total coliforms; 13% and 25% for faecal coliforms; 69% and 80% for faecal streptococci (Guide standard); 50% and 67% for salmonellae and 73% and 88% for enteroviruses. There was a significant overall increase in the mean number of symptoms reported for each child (p < 0.001). However, the prevalence of certain symptoms increased significantly only in those children who had been in contact with the water on the day of the beach interview. These symptoms included vomiting (p < 0.0009), diarrhoea (p < 0.0001), itchy skin (p < 0.0009), fever (p < 0.0013), lack of energy (p < 0.0007), and loss of appetite (p < 0.0227). None of the other variables investigated could account for the significant increase in the reported symptom experience of those children in contact with sea water contaminated with sewage. CONCLUSIONS--Children who come into contact with contaminated sea water are likely to develop symptoms as a result.     

Persistence of Escherichia coli O157:H7 in dairy cattle and the dairy farm environment.

The persistence of Escherichia coli O157:H7 in cattle and the farm environment was investigated on eight Ontario dairy farms positive for E. coli O157:H7 in a longitudinal study commenced one year previously. Faecal samples from cows, calves, humans, cats, rodents, wild birds, a composite fly sample and numerous composite and individual environmental samples were cultured and tested for verotoxin-producing E. coli (VTEC). VTEC isolates were serotyped and E. coli O157:H7 isolates were phage typed. E. coli O157:H7 phage type 34 was isolated from one calf on each of two farms. The same phage type had been isolated on one of these farms 12 months earlier. Most E. coli O157:H7-positive animals and farms became culture-negative within 2 and 3 months, respectively. E. coli O157:H7 was not isolated from any environmental samples, although evidence of VTEC was found in composite samples from calf feeders (19.1%), calf barn surfaces (18%), cow feeders (14.9%), flies (12.5%), cow barn surfaces (11.3%), and individual milk filters (12.5%). VTEC belonging to 21 non-O157 serotypes were isolated from 24 cows (8.2%), 21 calves (18.3%), 2 cow feeder samples (3.0%), and 1 calf feeder sample (4.8%). Shedding of E. coli O157:H7 by infected dairy cattle appears to be transient and persistence of E. coli O157:H7 was not demonstrated from the farm environment sites tested.     

Salmonellosis in North Thames (East), UK: associated risk factors.

We assessed the rate of salmonella infections and risk factors associated with infection in North East Thames in 1993. Cases of culture confirmed infection were identified through microbiology laboratories and environmental health officers in the North East Thames. A total of 1730 cases were reported and 209 of these individuals (those who could be contacted within a 3-week interval after onset of symptoms) and matched controls were interviewed by telephone. In addition randomly selected controls were interviewed over a 4-month period about recent gastric acid lowering medication and antimicrobial ingestion. Sixty-six serotypes were identified: S. enteritidis was isolated from 1179 (69%) cases, S. typhimurium from 221 (13%), S. virchow from 77 (4%) and S. newport 25 (1%). Infections were more frequent in summer months. Highest rates were documented in children under 2 years of age for S. enteritidis (108/100,000) and under 1 year for S. typhimurium (36/100,000). Using the Townsend score, highest isolation rates of S. enteritidis were in more prosperous areas (36/100,000 vs. 27/100,000; odds ratio (OR) 1.3, 95% confidence intervals (CIs) 1.2-1.6, P < 0.0001), while for S. typhimurium, there was no relation between deprivation index and isolation rates areas (6.4/100,000 vs. 6.1/100,000; OR 1.1, 95% CIs 0.8-1.5, P = 0.77). The case control study showed a significant association between ingestion of products containing raw eggs and S. enteritidis infection (8/111 cases vs. 0/110 controls; OR undefined, lower 95% CIs 3.4). Individuals with salmonella infection were significantly more likely to have travelled abroad in the week before the onset of illness [42/186 (23%) vs. 1/182 (0.5%); OR 40, 95% CIs = 5.5-291, P < 0.001] and to report gastroduodenal disease [11/143 (7%) vs. 3/143 (2%); OR 5.0, 95% CIs = 1.1-23, P = 0.04]. There was an association between illness and gastric acid-lowering medications [unmatched controls OR 22.3 (95% CIs 1.5-3.7, P = 0.0002), matched controls OR 3.7 (95% CIs 1.0-3.8, P = 0.07)], but no association with antimicrobial ingestion.